With rapid development of display technique, a touch screen panel has been widely applied in daily lives. At present, the touch screen may be divided according to their composition structures as follows: an add-on mode touch panel, an on-cell touch panel and an in-cell touch panel. The add-on mode touch panel is formed by separately producing a touch screen and a display screen and then jointing them together to constitute a display screen with a touch function. The in-cell touch panel embeds touch electrodes of the touch screen within the display screen, which may reduce the whole thickness of the modules and greatly decrease cost for manufacturing the touch screen, so it is favored by various venders of the panels. In the in-cell touch panel, a mutual-capacitance touch screen becomes a main stream of the current in-cell touch panel due to its higher sensitivity and an advantage of multi-points touching.
Particularly, the in-cell touch panel is a device in which touch scanning lines and touch sensing lines in the touch screen are integrated in the display screen. For example, the touch scanning lines and the touch sensing lines are integrated in a liquid crystal display (LCD) or an organic light emitting device (OLED). In a conventional design as shown in FIG. 1, a touch scanning signal on the touch scanning lines Txn (n=1, 2, 3, . . . ) is transferred through wires in a marginal frame by an external driver (IC). However, with increased size of the display screen, a quantity of the touch scanning lines Txn are increased and wires for transferring touch scanning signals to the touch scanning lines are correspondingly increased, which leads to spaces occupied by the wires are also increased and limits applications of the in-cell technique to a display screen with a large size and a narrow marginal frame.
In order to solve the issues as mentioned above, at present, a touch driving circuit for outputting a touch scanning signal to the touch scanning lines is usually integrated on an array substrate to omit wires in the marginal frames of the display so as to implement a display screen with a large size and a narrow marginal frame. Thus, it is urgent to provide a touch driving circuit integrated on the array substrate and having a simple configuration.